According to Caryl (in her comment to this post), Rvies-Blanques has been blogging since May of 2003 (currently, the distinction of "oldest winery blog" belongs to Winemaker's Diary by David Coffaro, with entries dating back to September, 1998).

My primary complaint with the Rives-Blanques blog is that it doesn't have an RSS feed , which is one of the essential features of a modern blog. I will willingly subscribe (using Bloglines) to every winery blog I know of and read it faithfully, but I am unwilling to visit a site without an RSS feed just to see if something new has been posted.

I would strongly recommend that wineries with "old school" online diaries convert to a modern blogging tool (TypePad, WordPress, Blogger, Movable Type), and make their first post a link to entries from their old system. Most of the bloggins wineries on our list are using TypePad (which I recommend) or Blogger (free). Only two lack RSS feeds.

If you want people to read your blog, you should make it as convenient as possible for them to do so. Does that sound like a lot of work? Then don't blog - your time will be better spent elsewhere.